Caps E2E suite size by computing per-test ROI - (regressions caught × value) ÷ (runtime × flake rate × maintenance) - then ranks every end-to-end test and recommends which bottom-decile ones to retire, move to a lower layer, or fix. Use when CI is slow or E2E-dominated, flaky failures are rising, or quarterly to keep suite size within maintenance capacity. For strategic unit:service:UI layer ratios use test-pyramid-balancer, for the minimal per-deploy critical-path gate use smoke-suite-gate, and for quarantining flaky tests use flaky-test-quarantine; this prunes low-signal tests by ROI.